Viscous Asymptotically Flat Reissner-Nordstr\"om Black Branes

We study electrically charged asymptotically flat black brane solutions whose world-volume fields are slowly varying with the coordinates. Using familiar techniques, we compute the transport coefficients of the fluid dynamic derivative expansion to first order. We show how the shear and bulk viscosities are modified in the presence of electric charge and we compute the charge diffusion constant which is not present for the neutral black p-brane. We compute the first order dispersion relations of the effective fluid. For small values of the charge the speed of sound is found to be imaginary and the brane is thus Gregory-Laflamme unstable as expected. For sufficiently large values of the charge, the sound mode becomes stable, however, in this regime the hydrodynamic mode associated with charge diffusion is found to be unstable. The electrically charged brane is thus found to be (classically) unstable for all values of the charge density in agreement with general thermodynamic arguments. Finally, we show that the shear viscosity to entropy bound is saturated, as expected, while the proposed bounds for the bulk viscosity to entropy can be violated in certain regimes of the charge of the brane.Comment: 28 pages, 2 figure. v3: Small changes and a few typos correcte

CATCH REGULATION AND ACCIDENT RISK: THE MORAL HAZARD OF FISHERIES' MANAGEMENT

A theoretical model focusing on the interaction between safety and fishery regulation is introduced in order to discuss the fishing units' behavior and the public policies' effect upon fatality rates and cost efficiency in the industry. The optimal welfare outcomes for a nontransferable and transferable vessel quota regime are compared and possible advantages and disadvantages of practicing these fishery regulations are identified. Among other things, the authors recommend the public authorities pay attention to moral hazard effects which may follow when the levels of public risk reducing services are increased.Research Methods/ Statistical Methods, Resource /Energy Economics and Policy,

Risk Attitudes and Individual Transferable Quotas

An analysis of ITQ fisheries management is offered in which two different groups of agents facing uncertain harvesting costs take part. The first group, termed as the coastal fleet, is risk averse, while the second group, interpreted as the ocean fleet, is risk neutral. In contradiction to what is seen in deterministic models of quota markets, given strongly decreasing absolute risk aversion amongst the coastal fleet members, it is found that the initial quota allocation affects the equilibrium quota price and the final catch distribution influencing the economic efficiency in the fishing industry.Transferable quotas, risk attitude, fishery management., D8, H2, Q2, Risk and Uncertainty,

The Crowding-Out of Work Ethics

This paper analyses optimal contracts in a principal-agent model where the agent is intrinsically motivated at the outset and there is an endogenous relationship between the structure of incentive payments and intrinsic motivation (crowding effects). The analysis shows that crowding effects have implications for the optimal contract and that under some conditions the principal can do better without implementing any economic incentives. Furthermore, it is shown that when high-powered incentives diminish intrinsic motivation (crowding-out) the first-best solution in a principal-agent framework is unattainable.Agency theory; intrinsic motivation; crowding effects